The IEEE 802.3 standard requires that an Ethernet node transmitting frames on the physical media provide a minimum “idle” time between the transmission of consecutive frames. An idle time or inter-packet gap is provided before transmission of a next frame starts in an attempt to allow a relatively small time interval for receiver electronics in each of the nodes to settle after completion of a previous frame. For example, an idle time of 9.6 μs may be provided between transmission of consecutive frames in some networks.
A node may start transmission of a frame by sending an 8 byte (i.e., 64 bit) preamble sequence. The preamble sequence may consist of 62 alternating 1's and 0's followed by the pattern ‘11’. Although each node in a system is required to provide the idle time between the transmission of frames, receiving nodes may not see a silent period or inter-packet gap equal to the full idle time. A repeater element between a source and destination node may lose preamble bits if trying to synchronize an incoming packet. Accordingly, repeater elements between the source and destination node need to regenerate the lost bits of the preamble. The time required for the repeater elements to regenerate the lost bits may cause a reduction in the inter-packet gap between frames.
Receiving adapters at nodes may attempt to address the reduction in the inter-packet gap by beginning to detect link activity within a time period at least equal to the inter-packet gap after the end of the previous frame. However, most adapters are capable of beginning detection before the inter-packet gap period expires. If the reduced inter-packet gap is less than the amount of time required by the receiving node before detecting link activity between two consecutive packets, the receiving adapter sees the two consecutive packets as a single packet, drops the two consecutive packets together, and accounts the drop as a single cyclic redundancy check (CRC) error.
Conventionally, detecting that two consecutive packets are missing has been relatively difficult based only on the packet loss statistics reported by transmission control protocol (TCP) and other protocols. IP traces may be used to confirm the loss of two consecutive packets, but an IP tracing method requires more debugging. Conventional solutions for detecting and correcting the loss of two or more consecutive packets require manual intervention by a user including checking network elements' inter-packet gap settings, cable lengths, number of repeating elements, etc. Accordingly, until a user implements these changes, network traffic may be adversely affected. For example, if TCP loses packets due to inter-packet gap problems, at least two packets need to be retransmitted. Because two packets are dropped, a timeout event is retransmitted thereby causing a larger reduction in the throughput of a connection.